React Events: Bind And Dispatch
REACT Events
function setInitialDOMProperties(tag, domElement, rootContainerElement, nextProps, isCustomComponentTag) {
for (var propKey in nextProps) {
if (!nextProps.hasOwnProperty(propKey)) {
continue;
}
var nextProp = nextProps[propKey];
if (propKey === STYLE$1) {
{
if (nextProp) {
// Freeze the next style object so that we can assume it won't be
// mutated. We have already warned for this in the past.
Object.freeze(nextProp);
}
}
// Relies on `updateStylesByID` not mutating `styleUpdates`.
setValueForStyles(domElement, nextProp);
} else if (propKey === DANGEROUSLY_SET_INNER_HTML) {
var nextHtml = nextProp ? nextProp[HTML] : undefined;
if (nextHtml != null) {
setInnerHTML(domElement, nextHtml);
}
} else if (propKey === CHILDREN) {
if (typeof nextProp === 'string') {
// Avoid setting initial textContent when the text is empty. In IE11 setting
// textContent on a <textarea> will cause the placeholder to not
// show within the <textarea> until it has been focused and blurred again.
// https://github.com/facebook/react/issues/6731#issuecomment-254874553
var canSetTextContent = tag !== 'textarea' || nextProp !== '';
if (canSetTextContent) {
setTextContent(domElement, nextProp);
}
} else if (typeof nextProp === 'number') {
setTextContent(domElement, '' + nextProp);
}
} else if (propKey === SUPPRESS_CONTENT_EDITABLE_WARNING || propKey === SUPPRESS_HYDRATION_WARNING$1) {
// Noop
} else if (propKey === AUTOFOCUS) {
// We polyfill it separately on the client during commit.
// We could have excluded it in the property list instead of
// adding a special case here, but then it wouldn't be emitted
// on server rendering (but we *do* want to emit it in SSR).
} else if (registrationNameModules.hasOwnProperty(propKey)) {
if (nextProp != null) {
if (true && typeof nextProp !== 'function') {
warnForInvalidEventListener(propKey, nextProp);
}
ensureListeningTo(rootContainerElement, propKey);
}
} else if (nextProp != null) {
setValueForProperty(domElement, propKey, nextProp, isCustomComponentTag);
}
}
}
function ensureListeningTo(rootContainerElement, registrationName) {
var isDocumentOrFragment = rootContainerElement.nodeType === DOCUMENT_NODE || rootContainerElement.nodeType === DOCUMENT_FRAGMENT_NODE;
var doc = isDocumentOrFragment ? rootContainerElement : rootContainerElement.ownerDocument;
listenTo(registrationName, doc);
}
function listenTo(registrationName, mountAt) {
var isListening = getListeningForDocument(mountAt);
var dependencies = registrationNameDependencies[registrationName];
for (var i = 0; i < dependencies.length; i++) {
var dependency = dependencies[i];
if (!(isListening.hasOwnProperty(dependency) && isListening[dependency])) {
switch (dependency) {
case TOP_SCROLL:
trapCapturedEvent(TOP_SCROLL, mountAt);
break;
case TOP_FOCUS:
case TOP_BLUR:
trapCapturedEvent(TOP_FOCUS, mountAt);
trapCapturedEvent(TOP_BLUR, mountAt);
// We set the flag for a single dependency later in this function,
// but this ensures we mark both as attached rather than just one.
isListening[TOP_BLUR] = true;
isListening[TOP_FOCUS] = true;
break;
case TOP_CANCEL:
case TOP_CLOSE:
if (isEventSupported(getRawEventName(dependency))) {
trapCapturedEvent(dependency, mountAt);
}
break;
case TOP_INVALID:
case TOP_SUBMIT:
case TOP_RESET:
// We listen to them on the target DOM elements.
// Some of them bubble so we don't want them to fire twice.
break;
default:
// By default, listen on the top level to all non-media events.
// Media events don't bubble so adding the listener wouldn't do anything.
var isMediaEvent = mediaEventTypes.indexOf(dependency) !== -1;
if (!isMediaEvent) {
trapBubbledEvent(dependency, mountAt);
}
break;
}
isListening[dependency] = true;
}
}
}
function trapBubbledEvent(topLevelType, element) {
if (!element) {
return null;
}
var dispatch = isInteractiveTopLevelEventType(topLevelType) ? dispatchInteractiveEvent : dispatchEvent;
addEventBubbleListener(element, getRawEventName(topLevelType),
// Check if interactive and wrap in interactiveUpdates
dispatch.bind(null, topLevelType));
}
function dispatchEvent(topLevelType, nativeEvent) {
if (!_enabled) {
return;
}
var nativeEventTarget = getEventTarget(nativeEvent);
var targetInst = getClosestInstanceFromNode(nativeEventTarget);
if (targetInst !== null && typeof targetInst.tag === 'number' && !isFiberMounted(targetInst)) {
// If we get an event (ex: img onload) before committing that
// component's mount, ignore it for now (that is, treat it as if it was an
// event on a non-React tree). We might also consider queueing events and
// dispatching them after the mount.
targetInst = null;
}
var bookKeeping = getTopLevelCallbackBookKeeping(topLevelType, nativeEvent, targetInst);
try {
// Event queue being processed in the same cycle allows
// `preventDefault`.
batchedUpdates(handleTopLevel, bookKeeping);
} finally {
releaseTopLevelCallbackBookKeeping(bookKeeping);
}
}
function getListener(inst, registrationName) {
var listener = void 0;
// TODO: shouldPreventMouseEvent is DOM-specific and definitely should not
// live here; needs to be moved to a better place soon
var stateNode = inst.stateNode;
if (!stateNode) {
// Work in progress (ex: onload events in incremental mode).
return null;
}
var props = getFiberCurrentPropsFromNode(stateNode);
if (!props) {
// Work in progress.
return null;
}
listener = props[registrationName];
if (shouldPreventMouseEvent(registrationName, inst.type, props)) {
return null;
}
!(!listener || typeof listener === 'function') ? invariant(false, 'Expected `%s` listener to be a function, instead got a value of `%s` type.', registrationName, typeof listener) : void 0;
return listener;
}